The primary purpose of railroad repair machinery is to reduce the man hours typically required to assemble and repair railroad track. Apparatus specifically designed to remove and replace used or unwanted track with new preassembled sections of track is not unknown. However, the prior art discussed herein still contains certain disadvantages that my apparatus has remedied.
U.S. Pat. No. 4,270,456 issued to Theurer utilizes a first transport vehicle designed for exclusive travel on existing railroad track, having an elongated girder with an elongated carrier arm pivotally mounted on each end thereof. The girder is supported in spaced relation above the first transport vehicle by four C-shaped gantries which are pivotally connected to the transport vehicle and the elongated girder. A trolley system is connected beneath the girder and arms and conveys track from a second transport vehicle to beyond the forward end of the first transport vehicle. The gantries are bowed to permit wide sections of preassembled track such as points and crossings to be moved along the guides.
U.S. Pat. No. 4,827,848 issued to Kusel teaches of a method for replacing a preassembled track section utilizing gantries and temporary track. The process of laying the temporary track and setting the fixed gantries is very time consuming requiring the temporary track to be winched back and forth from its transport vehicle.
U.S. Pat. No. 4,773,332 issued to Theurer et al discloses an apparatus for replacing elongated track sections. The invention includes a lower transport vehicle for carrying the track sections and at least one gantry carriage for raising and lowering various track sections. The lower transport has a plurality of flanged wheels for travel on existing track sections and a set of tracked conveyors for travel along a horizontal grade. Though pivotally mounted, the tracked conveyors are centrally located beneath the transport and operate from vertical axis located along the longitudinal axis of the transport. The gantry carriages rest atop and are secured to the track to be lifted and have laterally and vertically distendable jacks that lift such track.
U.S. Pat. No. 4,249,467 issued to Theurer et al discloses two carriage sections slidably connected to an elongated girder which is supported intermediate the two carriages and has a hoist mounted thereunder. The carriages are primarily supported on flanged wheels for engagement with a track but have alternate tracked conveyors as well for horizontal movement over grade. The tracked conveyors are mounted beneath the carriage and not only support the bulky carriages but also the expansive guide system mounted therebetween.
The Gomaco GP-3500 4-TRACK is used for laying and smoothing road pavement has tracked conveyors that pivot 15 degrees from a forward longitudinal axis; however, this pivotal movement was only contemplated for minute adjustments in forward direction. The legs on the Gomaco paver can be adjusted upward no more than one foot and such adjustment is not contemplated to facilitate the lifting of objects suspended thereunder or the induction thereunder of transport means.